Motor controller



Dec. 26, 1922. 1,439,892.

A. J. HORTON.

MOTOR CONTROLLER.

FILED NOV. 24 1917.

Patented Dec. 26, 1922.

UNITED. STATES PATENT OFFICE.

ALBERT J. HORTON, OF WHITE PLAINS, NEW YORK, ASSIGNOR TO THE CUTLER- HA'MMER MFG. 00., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WIS- CONSIN.

MOTOR CONTROLLER.

Application filed November 24, 1917. Serial No. 203,667.

To all whom it may concern:

Be it known that I, ALBERT J. HORTON, a citizen of the United States, residing at lVhite Plains, in the county of Vvestchester and State of New York, have invented new and useful Improvements in Motor Controllers, of which the following isa full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

This invention relates to motor controllers.

More particularly the invention relates to starting and speed regulating apparatus by means of which the controlled motor may be automatically accelerated to any one of a number of predetermined speeds and thereafter subjected to speed regulation at will.

One of the objects of the invention is to provide a simplified controller for the aforesaid purposes and one wherein a common resistance will serve for both the starting and regulating means.

A further object is to provide a controller of the aforesaid character wherein the regulating means may be operated for speed variation after acceleration of the motor without necessitating any further operation of the starting means.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawing illustrates schematically and diagrammatically one cn'ibodiment of the invention which will now be described. it being understood that the invention is susceptible of various modifications falling within the scope of the appended claims.

The controller illustrated includes an electromagnetic main switch 1, an electromagnetically operated starting device 2 and a manually operable speed regulating device 3 controlling an armature resistance R and a field resistance R for a motor 4. The motor, as illustrated, is of the compound type, being provided with an armature A, a series field winding F, and a shunt field winding F.

The starting device 2 is of a well known type, comprising a rock shaft 5 carrying contact arms 6, 7 and 8, to respectively engage stationary contacts 9. 10 and 11. The arms 6, 7 and S are arranged on the shaft 5 in differentangular relations therewith and said shaft is operable by a solenoid 12 to cause said arms to engage theirrespective stationary contacts progressively. These contact arms are utilized, as hereinafter more fully set forth, to short circuit the armature resistance R to varying degrees according to the setting of the device 3 and the shaft 2 is further provided with a contact arm 13 cooperating with a stationary contact 14 to control a shunt around the field resistance R. The arm 13 is so arranged upon the shaft 5 as to engage contact 14 in the off position of the starting device 2 and to be dlsengaged therefrom simultaneously with or subsequent to engagement of contact arm 8 with contact 11. Thus the arm 13 and contact 14 provide for shunting field resistance until after acceleration of the motor through the medium of the armature resistance. Further, the starting device 2 includes a normally closed auxiliary switch 15 adapted to be tripped by an arm 16 on shaft 5 to insert a resistance r in circuit with the solenoid 12 upon full response of said solenoid.

25 for control .of armature resistance R.

Also, the arm 17 is provided with a brush 26 adapted to continuously engage a segment 27 and to bridge said segment with any one of a series of contact buttons 28 or a se ment 29 for control of the field resistance R". The arrangement is such that with the arm in the position illustrated it provides for in clusion of practically all of the armature resistance and exclusion of all of the field resistance while counter-clockwise IIIOYB- ment of said arm provides for gradual exclusion of the armature resistance and then gradual inclusion of the field resistance in the usual manner. 1

Thus barring interference by the starting device 2 it will be observed that the device 3 may be utilized for varying the speed of the motor at will by both armature and field regulation and as will now be described, said device 3 is designed to commutate the connections between the starting device and resistance R to enable said starting device to control said resistance but without interference with manual regulation of the latter. For such commutations the device is provided, with a segment 30 to be continuously engaged by a brush 31 on an extension of the arm 17, a segment 32 to be engaged by said brush when the arm engages contact button 22 or rests in any position to the right thereof and a segr ient 32-3 to be engaged by a brush 3%: on the arm when the latter engages button 24. And as will hereinafter appear, the circuit arrangement is such that the segments 30 and when bridged complete a connection from starter contact 9 to resistance button 22 while brush 3% when in engagement with segment 33 establishes a connection between starter contact 10 and resistance button 24:. On the other hand, positioning of. the arm to disengage segments 32 and 33 provides for interrupting such connections, thereby rendering the starter contacts 6-49 and ?-1O .inelliective to vary the resistance it, while the remaining starter contacts serve only to control the resistance ll through arm 17 and these provisionsthus limit the accelerating influence ot the starter according to the position of arm 17. I

The main switch 1 is. provided with main contacts 40 to complete the motor circuit, contacts e1 engaged when said switch is deenergized to establish a dynamic bra-king circuit for the motor including a breaking resistance H and auxiliary contacts 43 tobe engaged upon response of said switch. This main switch is controllable by a normally open push button switch 15 for energization and by a normally closed push button switch 46 for de-energization,the latter push button switch being included in a maintaining circuitfor said main switch including a resistance r.

Assuming the starting device to be in oil position and the speed regulating device to be in any positioiuclosure or the main switch completes circuit from line L by conductor H to and through all of the armature resistunce ll to segment 25, by comluctor 415% through the motor armature A, by conduc tor ell) through contarts ll) of said main switch, by comluctor it) through the series .lield winding F, by conductor 51 to line L. Thus the motor always started with all ot the armature resistance included in circuit therewith, and with the starting device in off position the shunt field circuit of themetor is completed to exclude all of the field resistance. This circuit may be traced from line L by conductor 52 to starter shaft 5 through arm 18 to contact 14, by conductors 58 and 54 to and through the shunt field windingF, by conductor 51 to line L.

Assuming the starter to be operated with the regulator arm 17 in the dotted line position, engagement. o1? starter contacts (S 9 etlects completion of circuit from line L by conductor 52 to starter shaft 5 and thence through said contacts by conductor to regulator segment 30, across brush 31 to segment 32, by conductor 56 to contact 22 and thence through the resistance R to the right of said contact to and through the motor armature and series held as already traced. This provides for short-circuiting the resistance ll; to the left of contact 22 and accordingly "for acceleration of the motor. Then when starter contact 710 engage, circuit may be traced from conductor 52 through starter shaft 5 and said contacts, by conductor 57 to the hub of arm 1'? and thence to segment 38 by conductor 58 to con tact button 2d and through the resistance R to the right thereof to and through the mo tor armature and series held, as already traced. This short circuits all resistance it to the left of button 2% and hence provides for further acceleration of the motor. And when starter contacts 8'11 engage circuit may be. traced from conductor 52 through shaft 5 and said contacts, by conductor 59 to segment 19 across brush 18 to segment 25 and thence directly to and through the motor armature and series field, thus short circuiting all of the starting resistance and acre atinp; the motor to normal speed. Also when contact arm 13 disengages contact 1.1 it interrupts the shunt around the field re sistance ll, but with the arm 17 positioned assumed it completes the field circuit en elusive of said resistance. This circuit may be traced from line L by conductors 47 and 60 to segment 2? across brush 26 to segment 29, by conductor 61 to and through the shunt field winding l? to line L, as already traced. @n the other hand, it will be apparent that upon interruption of the field resistance shunt any predetermined amount of field. resistance may be included b moving the arm 17 counter-cloclrwise.

Assuming that the motor be started with the arm 1'7 in engagement with contact 23, thus disengaging brush 3-1: from segment ill-l, engagement O'li'SlT'zll'lIEl' contacts (h-f) serves to short circiilit the arn'iuture resistance between buttons 20 and but engage;sent oi starter contacts l -ll) cll'ec no control oi' the resistance because of the interruption ot circuit between starter contact 1 and regulator contact. On the other hand, when the starter contacts 8 11 engage they complete the motor circuit from conductor 59, which leads from line llu to segment 19 and thence across brush 18 to contact 23 to and through the resistance between contacts 23 and 25 to the motor. Thus the operation of the starter merely effects rei'noval of the resistance to the left of the arm 17, leaving the resistance to the right of the arm in circuit for regulation ol 'the motor speed. And as will beapparent, movement of the arm 17 from'the dotted line position to the position last assumed, Zlflilifil' acceleration oi the motor to normal speed, would eliect the same circuit changes as those just described to include the same amount of armature resistance. Also, as will be apparent, greater movement of the arm from the dotted line position to disengage brush 34 from segment 33 would interrupt the connection between the starter and resistance button 22 thereby reincluding in the motor circuit all resistance to the right of said arm. Conversely starting of the motor with the arm to the left of contact 22, would render the starter contacts 6-9, as well as the starter contacts 710, ineifective to exclude any of the starting resistance so that operation of the starter would merely accelerate the motor to a degree corresponding with the exclusion of the resistance to the left of the arm 17, the remainder of the resistance being maintained in circuit for speed regulation. Accordingly the arm 17 may be set to limit the starter to exclusion of different amounts of the armature resistance, whereas after acceleration of the motor to normal speed a variable amount of armature resistance may be reincluded in the motor circuit by the arm 17 without interference from the starter and without any further operation of the latter.

Assuming closure of push button switch 45, circuit may be traced from line L by conductor 62 through the winding of main switch 1, by conductor 63 through said push button switch, by conductor 64 to line L. This provides for closure of said switch for completion of the motor circuit as above described and for completion of the circuit of starter solenoid 12. The latter circuit may be traced from line L by conductor 52 through starter shaft 5, by conductor 65 through switch 15, by conductor 66 through solenoid 12, by conductors 67 and 68 through the auxiliary and main contacts of switch 1 and thence through the series field winding to line L, as already traced. And when push button 45' is released the main switch is maintained energized by a circuit extending from conductor 63 through push button switch 46 and by conductors 69 and 68 to conductor 50 and thence through the motor field winding to line L. This provides for continued operation of the motor until push button switch 46 is depressed and upon full operation of the starter the same actuates its auxiliary switch 15 to reinsert resistance 7' in circuit with solenoid 12 to protect the latter during continued operation of the motor.

What I claim as new and desire to secure by Letters Patent is:

1. In a motor controller, in combination, an accelerating device and a speed regulating device, said devices having a common resistance to be controlled thereby and said speed regulating device having electrical means for commutating the circuit connections between said accelerating device and said resistance whereby said speed regulating device may be set to vary the limit of acceleration by said accelerating device and subsequently adjusted for independent regulation of said resistance.

2. In a motor controller, in combination, a starting and speed regulating resistance, a starting device for excluding said resistance in steps, a device for varying said resistance for speed regulation, said devices beingmechanically independent and commutatable electrical connections between said devices rendering said starting device subordinate to said speed regulating device.

3. In a motor controller, in combination, a starting and speed regulating resistance, a device for varying said resistance for speed regulation and a starting device for varying'said resistance in a step by step manner for acceleration, the latter device being I mechanically independent of said speed regulating device but being electrically connected to said resistance through said speed regulating device whereby its range of effectiveness is variable by said speed regulating device.

4:. In a motor controller, in combination, two resistance varying devices, one for starting and the other for speed regulation, a starting and speed regulating resistance common to said devices and having a plurality of connections with each for graduated control thereby and circuit commutating means associated with said speed regulating device for interrupting one or more of the connections between said resistance and said starting device according to the adjustment of said regulating device.

, 5. In a motor controller, in combination, a starting and regulating resistance, a starting device having a plurality of contacts for connection to said resistance and means to engage said contacts successively for exclu ding said resistance from circuit in a step by step manner, and. a device connected to said resistance and having an element ads justable to graduate said resistance for speed regulating purposes, said element being included in seriesbetween said resistance and. the last engaged contact of said starting device, said speed regulating device having means associated therewith to make and break connections betwee said resistance and other contacts of sai starting device according to the adjustment of said element.

6. In a motor controller, in combination, an armature resistance, a starting device connected to said resistance to exclude the same in steps for acceleration, and a device connected to said resistance and having an element adjustable to graduate said resistance for speed regulating purposes, said element being included in the connection finally established by said starting device and having means associated therewith to interrupt all connections between said starting device an armature resistance,;a. field resistance, an electromagnetically operated starting device normally shunting said field resistance and operable to exclude said armature resistance in steps and thereafter remove the shunt from said field resistance and a man.- ual adjusting device for both 01' said resistances, the latter devicebeing included in circuit between said starting device and said armature resistance for regulation of the amount of such resistance excluded by said starting device.

scribed my name.

ALBERT J. HORTUN. 

